The present invention is directed to bicycles and, more particularly, to bicycle devices that include an electrical component powered by a power supply.
Bicycle-mounted gearshift systems, and automatic gearshift systems in particular, comprise running condition (e.g., speed) detecting means for detecting the running condition of the bicycle, a gearshift apparatus, and gearshift control means for upshifting and downshifting the gearshift apparatus in accordance with the running condition of the bicycle. The gearshift control means typically comprises a motor or other electronic actuating device that automatically operates the gearshift apparatus. The electrical components usually are powered by a common DC power supply such as a dynamo or secondary cell. Bicycle computers used with such systems often have a liquid crystal display (LCD), for example, for displaying various types of information to the rider. Such information may include time, the bicycle speed, running distances, cadence (crank RPM), the gearshift position, and other information related to the running conditions.
Because the surrounding brightness differs between daytime and nighttime, there are cases when it is convenient to have the display operate differently when riding the bicycle at these times. For example, at night it is more difficult to view the display, so some bicycle computers are equipped with a backlight. The backlight may comprise a reflective panel disposed behind the liquid crystals of the display, and a light-emitting diode (LED) that directs light onto the reflective panel.